An imaging device includes: an optical element including a metal layer adapted to be brazed and arranged on an outer peripheral surface of the optical element; a first frame body including a metal part adapted to be brazed and arranged at least on an inner peripheral surface and an outer peripheral surface of the first frame body, the inner peripheral surface being brazed onto the outer peripheral surface of the optical element; and a second frame body including a metal part adapted to be brazed and arranged at least on an inner peripheral surface of the second frame body, the inner peripheral surface being brazed onto the outer peripheral surface of the first frame body. A coefficient of thermal expansion of the first frame body is closer to a coefficient of thermal expansion of the optical element than a coefficient of thermal expansion of the second frame body.